Section 2 (Exam 1)

Question 1

Solutes

Answer 1

things dissolved in a liquid

Question 2

solvent

Answer 2

liquid in which solutes are dissolved in

Question 3

Solution

Answer 3

solutes dissolve in a solvent to form a solution (both together)

Question 4

Passive Diffusion

Answer 4

simple diffusion
no ATP

net movement until the concentration is equal (dynamic equilibrium)

rapid over short distances

Question 5

T/F passive diffusion can occur in open space or through a partition

Answer 5

True

Question 6

What level of permeability through the membrane?

small molecules (CO2 and O2)

Answer 6

HIGH

Question 7

What level of permeability through the membrane?

charged molecueles and large polar molecules

Answer 7

cannot diffuse through lipid bilayers

Question 8

What level of permeability through the membrane?

small polar molecules (H2O)

Answer 8

have certain permeability,

usually have to helped

Question 9

Facilitated Diffusion

Answer 9

involves carriers, no energy,

ex) channels/ion channels

Question 10

Ion Channel Specificity

Answer 10

Selectivity Filter (size and charge )

Gates (open and closed)

Question 11

Ligand-Gated

Answer 11

binding of specific molecules to channel protein which changes the receptor shape and allows it to pass through (lock and key)

Question 12

Voltage Gated

Answer 12

changes in the voltage of a cell which blocks some molecules

Question 13

Mechanically-Gated Ion Channel

Answer 13

physically deforming the membrane may cause a conformational change

Question 14

Explain specificity and why it is important to maintain homeostasis

Answer 14

specificity allows the body to complete very specific tasks. If every messenger protein could do everything, then there would be choas and homeostasis would not exist.

specificity= ability of a channel protein binding site to bind a specific ligand

Question 15

Affinity

Answer 15

how ‘sticky’ a ligand is to its receptor

determines how likely it is that a bound ligand will leave

Question 16

How does affinity impact diffusion?

Answer 16

greater affinity= greater diffusion

the gate is open longer and allows more molecules to pass through

Question 17

Explain Carrier Mediated Facilitated Diffusion

Answer 17

movement with help from a conformational change of transporters

ex) glucose transporter

Question 18

What 4 factors determine rate of a substance?

Answer 18

1) concentration
2) affinity
3) # of transporters
4) how fast the receptor can change shape to grab more proteins

Question 19

what is saturation?

Answer 19

concentration of solute increases along with the concentration of receptors being filled

(all binding sites are occupied)

Question 20

I 0
I 0 x x x
I 0 x
I 0 x d d d d d
I 0 x d
I0xd__________________

(imagine the 0, x, and ds are all curved lines on a graph)
the y-axis is rate
the x-axis is concentration

Which is passive diffusion?
Which is Facilitated Diffusion (carrier mediated)?
Which is Facilitated Diffusion with Ion Channels?

Answer 20

0 is passive diffusion

d is Facilitated Diffusion (carrier mediated)
x Facilitated Diffusion with Ion Channels

Question 21

Why is carrier-mediated transport needed for glucose?

Answer 21

because glucose is so giant to the cell.
also its polar

Question 22

Why would midwives lick infants?

Answer 22

CYSTIC FIBROSIS!

Caused By: defect in the channel protein that normally transports Cl- ions

Protein: CFTR is located in airways, sweat glands and pancreas

CFTR CHANNEL IS ABSENT/DEFECTIVE
Cl- transport is broken

Question 23

In Cystic Fibrosis (in the Lung) the muscus becomes ______________, why?

Answer 23

lung mucus becomes super thick

Cl- (salty) can not leave, so Na+ can not leave. Water will always follows Na+ so water will stay in the cells instead of the lungs.

Lung mucous will dry out and create a bacteria haven that makes people get really sick.

Question 24

Why is cystic fibrosis still a thing?

Answer 24

because it is a genetically inherited disease which can be passed down from heterozygous parents that don’t even know they are carrying the gene.

Question 25

Why is a heterozygous person for Cystic Fibrosis more likely to survive Cholera

Answer 25

Cholera works by completely opening CfTR channels and constantly producing cAMP. If a person doesn't have many CFTR channels (heterozygous CF people) than the symptoms should be less than a regular person

Question 26

Active Transport. Tell me all about it.

Answer 26

Energy is used against concentration gradient substance must bind to a transporter in the membrane (transporter is usually called a pump) 2 types 1) Primary Active Transport (energy used by protein transporting) 2) Secondary Active Transport (energy used is indirect)

Question 27

In Primary active transport, transporter itself is an enzyme called _______ that catalyzes the breakdown of ATP

Answer 27

ATPase

Question 28

In Secondary Active Transport The movement of the helper ion (usually Na+) is _______and the movement of the actively transported solute being moved by the same protein is ________

Answer 28

downhill uphill

Question 29

Cotransport (symport) is ....

Answer 29

helper ion and solute moving in the same direction

Question 30

countertransport (antiport)

Answer 30

helper ion and solute moving in opposite direction

Question 31

Phagocytosis

Answer 31

cell eating

Question 32

pinocytosis

Answer 32

cell drinking

Question 33

in phagocytosis, extensions of the cell membrane (__________) fold around the surface of the particle engulfing it entirely

Answer 33

pseudopodia remember the psuedo foot from microbiology?

Question 34

pseudopodia + solute=

Answer 34

phagosomes

Question 35

pinocytosis occurs in all cells (T/F)

Answer 35

true

Question 36

pinocytosis is a very specific process where receptors go into the ECF and bring back exactly what the cell wants (T/F)

Answer 36

false, pinocytosis is very random, the cell has no idea what its drinking, it just drinks.

Question 37

receptor mediated endocytosis has something very specific about it, what is it?

Answer 37

clathrin links to ligand receptor and forms a clathrin coated pit which turns into a vesicle and is then dissolved. it allows cells to obtain ligands without ECF fluid

Question 38

clathrin receptors are recycled in Receptor Mediated endocytosis (T/F)

Answer 38

true

Question 39

what is an example of receptor mediated endocytosis?

Answer 39

iron and cholesterol

Question 40

what is Familial Hypercholesterolemia?

Answer 40

a genetic mutation in the LDL receptor, ApoB, or gene controlling the LDL receptor CAN NOT UPTAKE LDL/CHOLESTEROL INTO CELLS LDL remains in plasma and builds up in the arteries, (heart attacks etc)

Question 41

What 3 things do exocytosis accomplish?

Answer 41

1) restores amount of cell membrane 2) membrane impermeable molecules synthesized by the cells can be pooped out 3) a way to add new membrane components to the cell membrane

Question 42

What are the two types of Exocytosis?

Answer 42

1) Constitutive (all the time) EXAMPLE = AQUAPORINS 2) Regulated (specific drives) major way hormones are released ALSO MAJOR WAY CALCIUM IS RELEASED

Question 43

What type of molecules in a cell typically require exocytosis to be secreted?

Answer 43

polar/ large molecules

Question 44

What key ion is required for regulated exocytosis secretion?

Answer 44

calcium!

Question 45

T/F phagosome is the most common form of cells taking something in

Answer 45

False, phagocytosis only occurs in specialized cells